Up to now, a disc cartridge, having a disc-shaped recording medium, such as an optical disc, rotatably housed therein, and which is loaded on a disc recording and/or reproducing apparatus, is housed therein as a disc-shaped recording medium, has been in use extensively. This sort of the disc cartridge, comprising a disc-shaped recording medium, housed in a main cartridge body unit, can be loaded/unloaded for the disc recording and/or reproducing apparatus, with the disc-shaped recording medium in a protected state.
Meanwhile, the size of the disc cartridge has to be reduced to as small a value as possible, in keeping with the size of the disc-shaped recording medium, in order to reduce the size of the disc recording and/or reproducing apparatus, employing the disc cartridge, in order to provide for facilitated handling of the disc cartridge, and in order to save the cartridge material and hence the production cost.
A disc cartridge, reduced in size in keeping with the size of the disc-shaped recording medium, housed therein, is disclosed in, for example, the Japanese Laid-Open Patent Publication H11-353845 (Patent Publication 1). In this disc cartridge, disclosed in the Patent Publication 1, the lateral side thereof corresponding to the inserting end into the recording and/or reproducing apparatus, is substantially arcuate-shaped to reduce the size of the disc cartridge.
With the disc cartridge, disclosed in the Patent Publication 1, the reduction in size achieved is not sufficient.
In the disc cartridge, disclosed in the Patent Publication 1, a shutter member, adapted for opening/closing a recording/reproducing aperture, is biased in the closing direction, by a biasing member, for reliably closing the recording/reproducing aperture for reliably protecting the disc-shaped recording medium, housed in the main cartridge body unit. Since the biasing member, provided in the disc cartridge, is formed by a spring plate, elastically deformed when thrust, it may become difficult to cause the biasing member to be elastically deformed reliably to unlock and to cause movement of the shutter member.